Combination Method of Heating Device of Pot/Kettle

ABSTRACT

A combination method of a heating device of a pot/kettle includes pre-casting an electric heating tube or a magnetically conducting metal into an aluminum block. Then, the aluminum plate, the aluminum block and the pot/kettle are heated to reach a preset temperature. Then, the aluminum plate, the aluminum block and the pot/kettle are stamped at a high speed so that the aluminum plate between the pot/kettle and the aluminum block is compressed instantaneously so as to combine the aluminum block with the bottom of the pot/kettle tightly and closely.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a combination method of a heating device of a pot/kettle.

2. Description of the Related Art

A conventional electric cooker comprises an intermediate pot, an inner pot placed in the intermediate pot, and a heating device mounted on the bottom of the intermediate pot. When the electric cooker is energized, the inner pot is heated to reach a high temperature so as to cook food, such as rice, meat and the like. The heating device includes an electric heating tube. The intermediate pot is made of aluminum which has a better heat conductive feature. The aluminum is soft so that the intermediate pot usually has a greater thickness to increase the weight and the cost.

When the intermediate pot is made of stainless steel instead of aluminum, the electric heating tube is coated with an aluminum layer which is then combined with the intermediate pot made of stainless steel. The aluminum layer is combined with the intermediate pot by a high frequency. However, the aluminum layer and the intermediate pot are made of different material so that they only have a surface combination. Thus, when the heat from the electric heating tube is transmitted to the intermediate pot, the aluminum layer and the intermediate pot have different expansion and contraction coefficients so that the aluminum layer and the intermediate pot are expanded with different extents and are easily detached from each other. Thus, the electric heating tube is easily separated from the intermediate pot due to an accidental hit.

A conventional working method of a saucepan comprises inverting a pan with the bottom of the pan facing upward, placing an aluminum block on the pan, placing a stainless material on the aluminum block, performing a heating step, and performing a stamping step to form a product. Thus, the stainless material is combined with the pan by the aluminum block. However, the aluminum block is easily squeezed outward from the bottom of the pan during the stamping process, thereby decreasing the quality of the product.

BRIEF SUMMARY OF THE INVENTION

The primary objective of the present invention is to provide a combination method of a heating device of a pot/kettle, with an aluminum plate being disposed between a pot/kettle and an aluminum block, and with the pot/kettle being combined with the aluminum block by a high-speed stamping process. The combination method includes the following procedures: (1) pre-casting an electric heating tube or a magnetically conducting metal into an aluminum block; (2) performing a preheat step to heat the aluminum plate, the aluminum block and the pot/kettle to reach a temperature ranged between 200° C. and 450° C.; (3) providing a die assembly for placing the aluminum block, with the electric heating tube or the magnetically conducting metal facing downward; (4) placing the aluminum plate on the aluminum block; (5) placing the pot/kettle above the aluminum plate, with a bottom of the pot/kettle facing downward; (6) performing a high-speed stamping process to stamp a bottom of an interior of the pot/kettle at a high speed, to squeeze and rub the aluminum plate which is filled with the bottom of the pot/kettle; and (7) combining the aluminum plate and the bottom of the pot/kettle with the aluminum block tightly and closely to form a product.

Preferably, the aluminum block and the aluminum plate are placed into a heating furnace to perform the preheat step, and the pot/kettle is heated by a high frequency to reach a preset temperature and then placed on the die assembly to perform the high-speed stamping process.

Preferably, the die assembly is formed with a covering edge, and when the pot/kettle or an intermediate pot is placed on the aluminum plate, the covering edge of the die assembly seals a gap defined between the bottom of the pot/kettle or the intermediate pot and the aluminum block to prevent the aluminum plate from being squeezed outward, so that the aluminum plate is filled with the gap.

According to the primary advantage of the present invention, the preheat step is performed to reach the preset temperature, and the high-speed stamping process is then performed to form the product, so that the intermediate pot or the pot/kettle is combined with the aluminum block tightly and closely.

According to another advantage of the present invention, the aluminum plate and the intermediate pot or the pot/kettle are processed by the preheat step and the high-speed stamping process to have a forging effect, so that the bottom of the intermediate pot or the pot/kettle has a smooth surface without needing a secondary working process, thereby saving the working time and labor, and thereby decreasing the cost of fabrication.

According to a further advantage of the present invention, the product has a high quality and has a higher productivity.

Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is an exploded perspective view of an electric cooker manufactured by a method in accordance with the preferred embodiment of the present invention.

FIG. 2 is a flow chart showing combination of an intermediate pot of the electric cooker and a heating device in accordance with the preferred embodiment of the present invention.

FIG. 3 is a cross-sectional view showing the covering edge of the die assembly seals and covers a gap defined between the bottom of the intermediate pot and the aluminum block.

FIG. 4 is a perspective assembly view of the electric cooker as shown in FIG. 1.

FIG. 5 is a flow chart showing combination of a pot/kettle and a heating device in accordance with the preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is an exploded perspective view of an electric cooker manufactured by a method in accordance with the preferred embodiment of the present invention. An electric heating tube 11 is pre-cast into an aluminum block 1. There is provided with an intermediate pot 3 which is made of stainless material. It is difficult to combine two metallic elements made of different material. In the conventional method for combining two metallic elements made of different material, the combination of the two metallic elements is poor, and the productivity is low. In addition, the conventional method for combining two metallic elements needs more labors and has complicated working procedures, thereby increasing the cost of fabrication. Further, the quality of the product made by the conventional method is poor.

Referring to FIG. 2, a flow chart of combination of the intermediate pot 3 of the electric cooker and a heating device is shown. A die assembly 5 is provided. The die assembly 5 is formed with a covering edge 51 (see FIG. 3) for placing the aluminum block 1 which is pre-cast with the electric heating tube 11. Then, an aluminum plate 2 is placed on the aluminum block 1. Then, the intermediate pot 3 is placed on the aluminum plate 2. Then, the aluminum block 1, the aluminum plate 2 and the intermediate pot 3 are processed by a preheat step 4. After a preset temperature is reached, a high-speed stamping process 6 is performed to form a product 7.

The aluminum block 1 and the aluminum plate 2 are initially placed into a heating furnace and are heated to reach a preheat temperature ranged between 200° C. and 450° C. The intermediate pot 3 is heated by a high frequency. When the preset temperature of the preheat step 4 is reached, the high-speed stamping process 6 is performed by a helical stamping head. In the high-speed stamping process 6, the aluminum plate 2 is rapidly squeezed and rubbed by an upper die to combine the aluminum block 1 and the intermediate pot 3 tightly and closely.

Referring to FIGS. 3 and 4, the die assembly 5 is formed with the covering edge 51 to limit the aluminum plate 2 so as to prevent the aluminum block 1 from compressing the aluminum plate 2 (which is softened after the preheat step 4) to protrude outward from the bottom of the intermediate pot 3 during the high-speed stamping process 6. The covering edge 51 of the die assembly 5 seals and covers a gap 20 defined between the bottom of the intermediate pot 3 and the aluminum block 1 to limit the aluminum plate 2. In such a manner, when the bottom of the intermediate pot 3 is stamped during the high-speed stamping process 6, the aluminum plate 2 is stamped and is filled with the gap 20 rapidly. Thus, the bottom of the intermediate pot 3 is tightly and closely combined with the aluminum block 1 by the aluminum plate 2. In addition, when the aluminum plate 2 is stamped, the aluminum plate 2 only covers the bottom of the intermediate pot 3 and the periphery of the aluminum block 1 (as shown in FIG. 4), and will not being spilled outward from the aluminum block 1, thereby preventing from a further working procedures, including cutting and polishing.

Referring to FIG. 5 with reference to FIG. 2, the intermediate pot 3 is replaced by a pot/kettle 30 which is made of metallic or stainless material, and the electric heating tube 11 is replaced by a magnetically conducting ring 12. Thus, the method in accordance with another preferred embodiment of the present invention is available for a heating device of the pot/kettle 30 which is used for a gas burner or an electromagnetic burner. The aluminum block 1 is pre-cast with the magnetically conducting ring 12 which is made of a magnetically conducting metal. The aluminum block 1 pre-cast with the magnetically conducting ring 12, the aluminum plate 2 and the pot/kettle 30 are combined integrally. In combination, the aluminum block 1, the aluminum plate 2 and the pot/kettle 30 are processed by the preheat step 4. When the preheat temperature (ranged between 200° C. and 450° C.) of the preheat step 4 is reached, the aluminum block 1, the aluminum plate 2 and the pot/kettle 30 are placed on the die assembly 5. Then, the high-speed stamping process 6 is performed to form the product 7.

Referring to FIG. 5 with reference to FIG. 3, the most important feature of the present invention is in that the die assembly 5 is formed with a covering edge 51. The covering edge 51 of the die assembly 5 seals and covers the gap 20 defined between the bottom of the pot/kettle 30 and the aluminum block 1 to limit the aluminum plate 2. In such a manner, when the bottom of the pot/kettle 30 is stamped during the high-speed stamping process 6, the aluminum plate 2 is stamped and is filled with the gap 20 rapidly so that the aluminum block 1 will not be compressed out of the bottom of the pot/kettle 30 during the high-speed stamping process 6. Thus, the bottom of the pot/kettle 30 is tightly and closely combined with the aluminum block 1 by the aluminum plate 2, without producing any clearance between the bottom of the pot/kettle 30 and the aluminum block 1.

In the present invention, the aluminum block 1 is pre-cast with the electric heating tube 11 or the magnetically conducting ring 12. Then, the aluminum block 1 is placed into the die assembly 5 and located at the bottom of the die assembly 5. Then, the aluminum plate 2 is placed into the die assembly 5 and located above the aluminum block 1. Then, the intermediate pot 3 or the pot/kettle 30 is placed on the die assembly 5 and located above the aluminum plate 2, with the opening of the intermediate pot 3 or the pot/kettle 30 facing upward to facilitate the high-speed stamping process 6. Thus, the method of the present invention is available for a non-planar pot bottom and is performed conveniently and rapidly.

Accordingly, the preheat step 4 is performed to reach the preset temperature, and the high-speed stamping process 6 is then performed to form the product 7, so that the intermediate pot 3 or the pot/kettle 30 is combined with the aluminum block 1 tightly and closely. Thus, the method of the present invention makes the product 7 quickly, saves the worker's labor, has a high quality and is available for mass production.

In addition, be design of the die assembly 5, the aluminum block 1, the aluminum plate 2 and the intermediate pot 3 or the pot/kettle 30 are processed by the preheat step 4 and the high-speed stamping process 6 to have a forging effect, so that the product 7 has a smooth surface without needing further working procedures including cutting, grinding and polishing, thereby decreasing the cost of fabrication.

Further, the covering edge 51 of the die assembly 5 seals the gap 20 defined between the bottom of the intermediate pot 3 or the pot/kettle 30 and the aluminum block 1 to limit the aluminum plate 2. In such a manner, the aluminum plate 2 is squeezed and expanded during the high-speed stamping process 6, to fill the space between the bottom of the intermediate pot 3 or the pot/kettle 30 and the aluminum block 1, so that the bottom of the intermediate pot 3 or the pot/kettle 30 is tightly and closely combined with the aluminum block 1, without producing any clearance between the bottom of the intermediate pot 3 or the pot/kettle 30 and the aluminum block 1.

Further, the method of the present invention simplifies the working procedures to save the later labor and transportation, has a high quality and is available for mass production to enhance the productivity.

Further, when the method of the present invention is used to make the intermediate pot 3, the aluminum block 1 is pre-cast with the electric heating tube 11, and when the method of the present invention is used to make the pot/kettle 30, the aluminum block 1 is pre-cast with the magnetically conducting ring 12, the method of the present invention is used conveniently.

Although the invention has been explained in relation to its preferred embodiment(s) as mentioned above, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the present invention. It is, therefore, contemplated that the appended claim or claims will cover such modifications and variations that fall within the true scope of the invention. 

1. A combination method of a heating device of a pot/kettle, with an aluminum plate being disposed between a pot/kettle and an aluminum block, and with the pot/kettle being combined with the aluminum block by a high-speed stamping process, and the combination method comprising the following procedures: (1) pre-casting an electric heating tube or a magnetically conducting metal into an aluminum block; (2) performing a preheat step to heat the aluminum plate, the aluminum block and the pot/kettle to reach a temperature ranged between 200° C. and 450° C.; (3) providing a die assembly for placing the aluminum block, with the electric heating tube or the magnetically conducting metal facing downward; (4) placing the aluminum plate on the aluminum block; (5) placing the pot/kettle above the aluminum plate, with a bottom of the pot/kettle facing downward; (6) performing a high-speed stamping process to stamp a bottom of an interior of the pot/kettle at a high speed, to squeeze and rub the aluminum plate which is filled with the bottom of the pot/kettle; and (7) combining the aluminum plate and the bottom of the pot/kettle with the aluminum block tightly and closely to form a product.
 2. The method of claim 1, wherein the aluminum block and the aluminum plate are placed into a heating furnace to perform the preheat step, and the pot/kettle is heated by a high frequency to reach a preset temperature and then placed on the die assembly to perform the high-speed stamping process.
 3. The method of claim 1, wherein the die assembly is formed with a covering edge, and when the pot/kettle or an intermediate pot is placed on the aluminum plate, the covering edge of the die assembly seals a gap defined between the bottom of the pot/kettle or the intermediate pot and the aluminum block to prevent the aluminum plate from being squeezed outward, so that the aluminum plate is filled with the gap. 